There is no indication that weather contributed to the accident. The flight path of C-FTIW could not be accurately determined. However, the information available reveals that the aircraft was heading northeast at an altitude between 100and 300feet before initiating a climb and a right turn. A few seconds later, the aircraft stalled and crashed after travelling approximately another 600feet, in a slight nose-up attitude and banked slightly right. The information gathered did not reveal the direction the aircraft banked before it crashed. However, analysis eliminated that ambiguity. If the aircraft had been banked steeply to the left, aerodynamic forces would have pushed it to the left of its flight path, that is, to the west of the lake, and it would have crashed in the trees. The attitude of the aircraft on impact and the marks on the ground indicate that the forces acting on the aircraft were directed toward the right. For that reason, it was concluded that the aircraft was banked right before it disappeared behind the trees. Therefore, it is reasonable to think that the pilot made a right turn after the low-altitude pass in order to continue on his route to Wabush.Analysis There is no indication that weather contributed to the accident. The flight path of C-FTIW could not be accurately determined. However, the information available reveals that the aircraft was heading northeast at an altitude between 100and 300feet before initiating a climb and a right turn. A few seconds later, the aircraft stalled and crashed after travelling approximately another 600feet, in a slight nose-up attitude and banked slightly right. The information gathered did not reveal the direction the aircraft banked before it crashed. However, analysis eliminated that ambiguity. If the aircraft had been banked steeply to the left, aerodynamic forces would have pushed it to the left of its flight path, that is, to the west of the lake, and it would have crashed in the trees. The attitude of the aircraft on impact and the marks on the ground indicate that the forces acting on the aircraft were directed toward the right. For that reason, it was concluded that the aircraft was banked right before it disappeared behind the trees. Therefore, it is reasonable to think that the pilot made a right turn after the low-altitude pass in order to continue on his route to Wabush. Aircraft It is possible that an unidentified mechanical problem increased the pilot's workload and distracted him before the impact. However, the aircraft maintenance records and the physical evidence at the accident site suggest that the accident was not caused by a mechanical failure. Examination of the propellers established that they were being driven by the engines and they were rotating at the same speed. Since the flaps were retracted, it was concluded that the aircraft did not experience an asymmetrical flap problem. No anomalies were observed by the witnesses or noted on previous flights that could have caused a loss of control. The wings and the vertical tail of the aircraft were equipped with vortex generators in accordance with STC SA00192SE. This modification altered the lift characteristics of the wing by increasing the stall angle of attack. To determine the effect of the vortex generators on the stall angle of attack, the modified wings had to be compared with the original wings. The results showed that the difference between the two stall angles of attack was about 2. This difference did not have a crucial effect on the lift conditions in this occurrence and it can be concluded that the aircraft was in a stall condition at the time of impact. Obstacle Clearance Margin The altitude of the aircraft the second time it overflew the area could not be determined with precision. However, it is possible that the aircraft was below the minimum obstacle clearance altitude before it stalled. To prevent CFIT accidents,2 CARs require that commercial flights operating under Subpart703 maintain a minimum obstacle clearance altitude. The rules for obstacle clearance are independent of the VFRweather minima. Plausible Scenarios Three scenarios were examined as plausible explanations for the loss of control of the aircraft before impact. Flight Control Failure Failure of the ailerons, rudder, or elevator was considered. In this occurrence, failure of the ailerons or rudder would not have resulted in loss of control of the aircraft. However, if the elevator failed, the result would be a nose-down attitude and an increase in speed. This would have caused the aircraft to strike the frozen surface of the lake at high speed with a steep angle of descent. If that had happened, most debris would be close to the point of impact. However, instead, the aircraft was in a slightly nose-up attitude, and the wreckage trail was over 250feet long. Consequently, failure of a flight control is not very plausible. Collision with a Tree The altitude of the aircraft during the pass and the cylindrical imprint near the right wing tip suggest that the aircraft might have struck a tree before crashing. If that had happened, the tree impact would have caused the aircraft to yaw right and pitch down. Given the altitude at which the collision would have occurred, it is reasonable to think that the pilot would not have had time to regain control of the aircraft before it struck the frozen surface of the lake. Moreover, a collision with a tree would have reduced the aircraft speed below the stall speed. However, no wood residue was found in the wing, the right wing tip remained attached to the wing until the final impact, and the imprint could be the result of a propeller blade impact during the aircraft breakup. Consequently, it is not possible to conclude with certainty that the aircraft struck a tree. Aerodynamic Stall Analysis of the impact marks, the wreckage pattern and the imprints on the aircraft's instruments3 indicates that the aircraft struck the frozen surface of the lake at a speed near the stall speed at an angle of descent consistent with the stall angle of attack of the aircraft. For these reasons, it can be concluded that the aircraft was in a stall condition at the time of impact. It is possible that the aircraft stalled during the climbing turn to the right. Several factors may have contributed to reducing the margin between the aircraft's speed and its stall speed. Since the pilot's aim was to fly over the cottage of his friends, it is reasonable to think that the aircraft was flying below normal cruising speed. Furthermore, the aircraft proximity to the ground could create an illusion of high speed, which may have induced the pilot to reduce speed. In addition, the throttle setting during the climb may have been the same as in the level flight segment, since the engine noise did not increase; if that were the case, the aircraft would have experienced a loss of speed during the climb. Finally, the observed steep bank turn substantially raised the stall speed. If the bank angle of the aircraft was 70, as was reported by one witness, the stall speed would have increased from 67knots to 115knots. Because the stall occurred during the climb, the left wing stalled before the right wing. Since the stall warning system is on the leading edge of the right wing, it is plausible that the audible signal alerted the pilot to the imminent stall less rapidly than if the stall had occurred in level flight. There was insufficient altitude for the aircraft to effect a recovery and the pilot did not have enough time to regain control of the aircraft. The following TSB Engineering Branch Laboratory reports were completed: LP 034/2007 - Propeller Analysis LP 035/2007 - Flap Actuator & Analysis LP 036/2007 - Instruments & GPS Analysis LP 055/2007 - Performance & Flight Analysis These reports are available from the Transportation Safety Board of Canada upon request. The aircraft stalled at an altitude that was too low for the pilot to recover.Finding as to Causes and Contributing Factors The aircraft stalled at an altitude that was too low for the pilot to recover. The aircraft was flying at an altitude that could lead to a collision with an obstacle and that did not allow time for recovery. The steep right bank of the aircraft considerably increased the aircraft's stall speed. The form used to record the pilot's flight time, flight duty time, and rest periods had not been updated for over a month; this did not allow the company manager to monitor the pilot's hours. At the time of the occurrence, the Aropro company operations manual did not make provision for the restrictions on daytime VFR flights prescribed in Section703.27 of the Canadian Aviation Regulations.Findings as to Risk The aircraft was flying at an altitude that could lead to a collision with an obstacle and that did not allow time for recovery. The steep right bank of the aircraft considerably increased the aircraft's stall speed. The form used to record the pilot's flight time, flight duty time, and rest periods had not been updated for over a month; this did not allow the company manager to monitor the pilot's hours. At the time of the occurrence, the Aropro company operations manual did not make provision for the restrictions on daytime VFR flights prescribed in Section703.27 of the Canadian Aviation Regulations. The fact that the aircraft was not equipped with a flight data recorder (FDR) or a cockpit voice recorder (CVR) limited the information available for the investigation and limited the scope of the investigation. Since the aircraft was on a medical evacuation (MEDEVAC) flight, the company mistakenly advised the search and rescue centre that there were two pilots on board the aircraft when it was reported missing.Other Findings The fact that the aircraft was not equipped with a flight data recorder (FDR) or a cockpit voice recorder (CVR) limited the information available for the investigation and limited the scope of the investigation. Since the aircraft was on a medical evacuation (MEDEVAC) flight, the company mistakenly advised the search and rescue centre that there were two pilots on board the aircraft when it was reported missing.